Yearly influenza epidemics continue unabated and are responsible for significant disease and financial burden. Influenza is a vaccine-preventable disease. It is also listed by NIAID as a high priority Category C emerging/reemerging infectious disease threat for which additional methods of prevention and treatment are sought. The primary goal of the original grant "Control of Epidemic Influenza" funded from 1997-2003 was to assess the potential of immunization of pre-school and school-aged children with influenza vaccine to control epidemic influenza through herd immunity. To address this aim, we performed an open-labeled, nonrandomized, community-based trial in children 18 months through 18 years of age with the investigational cold-adapted influenza vaccine, trivalent (CAIV-T). In the four vaccination years of the study we administered 18,780 doses of CAIV-T to 11,096 children. This represented annual vaccination coverage of 20-25 percent of age-eligible children. Some of our findings were 1) an indirect effectiveness (herd immunity) of 8-18 percent against influenza-associated illnesses in adults; 2) a single dose of CAIV-T in children was associated with significant protection that lasted through at least two influenza seasons, and 3) CAIV-T was safe and not associated with an increase in health care utilization. The goal of this renewal application is the control of epidemic influenza through immunization of school-aged children with CAIV-T, which may serve as an option for pandemic preparedness and biodefense. The specific aims are 1) to control the spread of influenza to susceptible adults greater than or equal to 35 years of age by vaccination of school-aged children. The adult age group is likely to benefit most from herd immunity during influenza epidemics. 2) To control the spread of influenza to susceptible children and young adults. Protection for this age group (<35 years of age) requires higher vaccination coverage before herd immunity is observed in the unvaccinated individuals. 3) To develop a school-based vaccination program for rapid and timely delivery of CAIV-T vaccine. A school-based influenza vaccination program could serve as a model for control of both influenza and other high priority pathogens. 4) To capture safety information of CAIV-T post-licensure. Our vaccination goal is 50 percent coverage each year (approximately 8,000 school-aged children). Emphasis will be placed on developing a school-based vaccination program. The trial will be a continuation of the open-labeled, non-randomized, community-based trial in central Texas which includes active viral surveillance in Scott & White clinics in the intervention and comparison communities, disease-based surveillance in Scott & White clinics in the intervention and comparison communities, and an integrated approach with local health department, medical establishment and news media to enhance the public awareness of influenza through dissemination of information to the medical establishment, general public, and news media outlets.